2019年8月
A centrally concentrated sub-solar-mass starless core in the Taurus L1495 filamentary complex
Publications of the Astronomical Society of Japan
- 巻
- 71
- 号
- 4
- 記述言語
- 英語
- 掲載種別
- 研究論文(学術雑誌)
- DOI
- 10.1093/pasj/psz051
- 出版者・発行元
- OXFORD UNIV PRESS
The formation scenario of brown dwarfs is still unclear because observational studies to investigate its initial condition are quite limited. Our systematic survey of nearby low-mass star-forming regions using the Atacama Compact Array (aka the Morita array) and the IRAM 30-m telescope in 1.2 mm continuum has identified a centrally concentrated starless condensation with a central H2 volume density of ∼106 cm-3, MC5-N, connected to a narrow (width ∼0.03 pc) filamentary cloud in the Taurus L1495 region. The mass of the core is ∼ {0.2-0.4} M_{☉ }, which is an order of magnitude smaller than typical low-mass pre-stellar cores. Taking into account a typical core to star formation efficiency for pre-stellar cores (∼20%-40%) in nearby molecular clouds, brown dwarf(s) or very low-mass star(s) may be going to be formed in this core. We have found possible substructures at the high-density portion of the core, although much higher angular resolution observation is needed to clearly confirm them. The subsequent N2H+ and N2D+ observations using the Nobeyama 45-m telescope have confirmed the high-deuterium fractionation (∼30%). These dynamically and chemically evolved features indicate that this core is on the verge of proto-brown dwarf or very low-mass star formation and is an ideal source to investigate the initial conditions of such low-mass objects via gravitational collapse and/or fragmentation of the filamentary cloud complex....
- リンク情報
- ID情報
-
- DOI : 10.1093/pasj/psz051
- ISSN : 0004-6264
- eISSN : 2053-051X
- ORCIDのPut Code : 77672126
- arXiv ID : arXiv:1904.05490
- Web of Science ID : WOS:000482425000007
- BibTex Code : 2019PASJ...71...73T